Opioids chronic

Even the most severe acute pain (that lasting hours to days) can usually be well controlled—with significant but tolerable adverse effects—with currently available analgesics, especially the opioids. Chronic pain (lasting weeks to months), however, is not very satisfactorily managed with opioids. It is now known that in chronic pain, presynaptic receptors on sensory nerve terminals in the periphery contribute to increased excitability of sensory nerve endings (peripheral sensitization). 

Dynorphin may also influence nociception at the spinal level. The levels of prodynorphin mRNA and immunoreactive dynorphin increase in the chronic inflammatory arthritic model (158). Dynorphin also inhibits morphine or P-endorphin-induced analgesia in naive animals and enhances analgesia in tolerant animals, indicating that this peptide may have a regulatory role in opioid analgesia (159). This effect does not appear to be mediated by a classical opioid receptor, since des-tyrosine dynorphin, which does not bind to opioid receptors, also antagonizes morphine analgesia (160). 

The major use of the narcotic analgesic is to relieve or manage moderate to severe acute and chronic pain. The ability of a narcotic analgesic to relieve pain depends on several factors, such as the drug, the dose, the route of administration, the type of pain, the patient, and the length of time the drug has been administered. Morphine is the most widely used opioid and an effective drug for... 

Opioid dependence rarely results ftom the prescribing of opioids temporarily for treatment of acute pain or pain of terminal illness. Even use in chronic... 

Carroll KM, Ball SA, Nich C, et al Targeting behavioral therapies to enhance naltrexone treatment of opioid dependence. Arch Gen Psychiatry 38 755-761, 2001 Centers for Disease Control and Prevention Recommendation for prevention and control of hepatitis (virus (HCV) infection and HCV-related chronic disease. MMWR Recommendations and Reports 47(RR19) l-39, 1998 Charney DS, Steinberg DE, Kleber HD, et al The clinical use of clonidine in abrupt withdrawal from methadone. Arch Gen Psychiatry 38 1273-1277, 1981 Charney D S, Heninger OR, Kleber H D The combined use of clonidine and naltrexone as a rapid, safe, and effective treatment of abrupt withdrawal from methadone. Am J Psychiatry 143 831-837, 1986... 

Carr DJ, Carpenter GW, Garza HH Jr, France CP, Prakash OM (1995) Chronic infrequent opioid exposure suppresses 1L-2R expression on rhesus monkey peripheral blood mononuclear cells foUowing stimulation with pokeweed mitogen. Int J Neurosci 81 137-148... 

Although controversial, findings as to how chronically administered morphine modulates neutrophil chemotaxis and function, a growing consensus believes that morphine is suppressive in the recruitment and functional aspects of these cells during an innate immune response. When peripheral human blood neutrophils were pretreated with exogenous opioids, lL-8-induced chemotaxis was inhibited (Grimm et al. 1998). Conversely, Simpkins et al. reported an increase in neutrophil chemotaxis... 

Considerable evidence for opioid-chemokine interactions comes from studies of pain and inflammation, where the inherent relationships between pain, inflammation, and the counteracting antinociceptive influences of opioids have considerable biomedical implications. The adaptive changes in immune and nervous system function with chronic inflammation and pain further reveal the inherent interrelatedness between opioids (Ossipov et al. 2003 Evans 2004 Roy et al. 2006 Christie 2008)... 

Christie MJ (2008) Cellular neuroadaptations to chronic opioids tolerance, withdrawal and addiction. Br J Pharmacol 154 384-396... 

Hutchinson MR, Coats BD, Lewis SS, Zhang Y, Sprunger DB, Rezvani N, Baker EM, Jekich BM, Wieseler JL, Somogyi AA, Martin D, Poole S, Judd CM, Maier SF, Watkins LR (2008) Proinflammatory cytokines oppose opioid-induced acute and chronic analgesia. Brain Behav Immun 22 1178-1189... 

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